The present invention relates to compounds useful for lowering the pour point of wax-containing liquid hydrocarbons, and the resulting compositions. In particular, the present invention is related to novel liquid hydrocarbon fuel compositions having improved properties.
Various types of wax containing distillate fuel oils such as diesel fuels, various oils of lubricating viscosity, automatic transmission fluids, hydraulic oil, home heating oils, and crude oils and fractions thereof require the use of pour point depressant additives in order to allow them to flow freely at lower temperatures. Often kerosene is included in such oils as a solvent for the wax, particularly that present in distillate fuel oils. However, increased demand for kerosene for use in jet fuel has led refiners to separate and recover kerosene thereby decreasing the amount of kerosene present in distillate fuel oils. This, in turn, has required the addition of a wax crystal modifier that would make up for the lack of kerosene. Moreover, the requirement for a pour point depressant additive in crude oils can be even more important since the addition of kerosene is not considered to be economically desirable. The present invention provides such advantages.
U.S. Pat. No. 5,707,943 to Covitch and assigned to the assignee of the present application teaches mixtures of esterified carboxy containing inter-polymers useful as pour point depressants in lubrication compositions.
U.S. Pat. No. 5,744,523, Barkowsky et al., Apr. 28, 1998, discloses that polyacrylate esters having an average molecular weight of 1500 to 20,000 may be manufactured by the transesterification of alkyl polyacrylates containing 1 to 4 carbon atoms in the alkyl group by free radical polymerization and, with
a) saturated or unsaturated aliphatic alcohols with 12 to 22 carbon atoms and PA1 b) optionally, additionally with dialkylaminoalkanols of the general formula HO--R.sup.1 --NR R.sup.2 R.sup.3, wherein R.sup.1 is a divalent alkylene groups with 2 to 4 carbon atoms and R.sup.2 and R.sup.3 are the same or different and represent alkyl groups with 1 to 4 carbon atoms, the molar ratio of the aliphatic alcohols a) to the dialkylaminoalcohols b) being 1:0 and 1:1.5, and the components a) and b) being used in such amounts, that 25 to 70% of the ester groups are transesterified. These materials are used as dispersants for finely divided solids, particularly for fillers and pigments, in organic media. PA1 R.sup.1 is an alkyl alkenyl or alkylphenyl group, PA1 n has an absolute value of 2,3, or 4 and average value of 2.0 to 2.5 and PA1 x is 10 to 200. PA1 (1) hydrocarbyl substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form a ring); PA1 (2) substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy); PA1 (3) hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain atoms other than carbon in a ring or chain otherwise composed of carbon atoms. Heteroatoms include sulfur, oxygen, nitrogen, and hetero substituents encompass substantially hydrocarbon chains containing heteroatoms, as well as cyclic substituents such as pyridyl, furyl, thienyl and imidazolyl groups. In general, no more than two, preferably no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituents in the hydrocarbyl group.
U.S. Pat. No. 5,633,325 (Esselborn et al., May 27, 1997); U.S. Pat. No. 5,583,184 (Esselborn et al., Dec. 10, 1996) and U.S. Pat. No. 5,571,872 (Esselborn et al., Nov. 5, 1996) disclose polymethacrylate esters, the ester groups of which in the .alpha. and optionally in the .omega. position differ from the ester groups in the chain. These patents also relate to a method for the synthesis of these compounds by transesterification under selected method conditions.
U.S. Pat. No. 5,296,573, Esselborn et al., Mar. 22, 1994, discloses polyacrylate esters with long-chain alkoxylated hydrocarbonoxy groups which can be obtained by the transesterification of polyacrylate esters with polyoxyalkylene monools, wherein the polyacrylate esters, up to 50% of which can be replaced by the corresponding methacrylate esters, have been obtained by free radical polymerization and wherein the polyoxyalkylene monools have the average formula EQU R.sup.1 O(C.sub.n H.sub.2n O--).sub.x H
wherein
The compounds can be used as emulsifiers, solubilizers and for thickening aqueous solutions containing anionic surfactants, particularly in cosmetics for personal grooming, and are distinguished by the content of low molecular weight components, which is smaller than that of the products obtained by copolymerization.
U.S. Pat. No. 5,225,481 (Gastinger et al., Jul. 6, 1993) and U.S. Pat. No. 5,021,506 (Gastinger et al., Jun. 4, 1991) disclose a stable, low viscosity polymer polyol composition comprising a continuous phase, a disperse phase within the continuous phase, and a dispersant for enhancing the stability of the resultant polymer polyol. In one embodiment, the dispersant is formed by polymerizing at least one acrylate monomer in a polyether polyol to form a single phase homogeneous liquid intermediate reaction product which is transesterified to form a polyol polyacrylate dispersant.
U.S. Pat. No. 5,145,914, Esselborn et al., Sep. 8, 1992, discloses polyacrylate esters with ammonium salt groups obtained by the transesterification of alkyl polyacrylates produced by free radical polymerization wherein the alkyl groups of the acrylate esters have 1 to 8 carbon atoms, up to 50% of the acrylate esters can be replaced by the corresponding methacrylate esters and the transesterification is carried out with
a) compounds of the formula ##STR1##
b) saturated or unsaturated aliphatic alcohols having 8 to 22 carbon atoms or alkoxylated alkylphenols having 9 to 27 carbon atoms in the alkylphenol group, wherein the molar ratio of component a) to component b) is 1:9 to 9:1, in such amount that 5 to 70% of the ester groups are transesterified and subsequently, the transesterified product is transformed into a salt. The new polyacylate esters with ammonium salt groups are distinguished by containing a lesser amount of low molecular weight compounds than products obtained through copolymerization and can be used as cationic surfactants and particularly, as active ingredients of metal adjuvents.